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ComfortSenset Model L7742U Touch Screen 7−Day Programmable Thermostat
Page 5
Controlling the Heat/Cool Modes of Operation
On initial power up or after an a power loss over 2
hours, the thermostat powers up at the HOME
screen in the AUTO position. If it powers up after a
power loss of less than 2 hours, it assumes the last
mode set. Pressing MODE repeatedly scrolls
through all the modesĊAUTO, EM HEAT, COOL,
HEAT, then back to OFF.
HEAT, COOL and OFF modes are as each name implies. AUTO
(autochangeover) allows the thermostat to switch between Heating
and Cooling, whichever mode is dictated by the indoor temperature.
EM HEAT (emergency heat) bypasses the first stage of heating (any
stage[s] of heat pump heating) and goes directly to the heat stage used
for maximum heating to more quickly warm a very cold house.
When the indoor temperature decreases or increases, the HEATING or
COOLING cycle will turn on based on the displayed mode. When the
HVAC system is on, the INFORMATION DISPLAY AREA (shown in fig-
ure 3) will display one or several operational messages (listed in the
table below). If the outdoor sensor is connected, and is turned on in both
installer and user settings, outdoor temperature will be included in the
displays. The table below summarizes the information messages.
When the faults, errors, and service information displays appear, dy-
namic keys will appear under the second line entries, REMIND,
CLEAR, SERVICE, or RESET. Press the box to perform the action.
INFORMATION DISPLAY AREA
Figure 3. Selecting Mode of Operation
Information Display Area table
Faults, Errors, and Service Information Operating Information
TEMP SENSOR ERROR, MEMORY ERROR
CALL FOR SERVICE
Top line: fault/error
Bot. line: action
SET DATE/TIME
Default DATE/TIME (MON JAN 1 12:00 PM)
[First time start up msg]
NO OUTDOOR SENSOR
CALL DEALER INFO
Top line: fault/error
Bot. line: action
HEATING, COOLING, HUMIDIFYING, DEHUMIDIFYING,
SYSTEM OFF, OUTDOOR TEMP xxF, INDOOR RH xx%,
MON SEP 24 3:OO PM
Top line: operation msgs
Bottom line: date & time
REPLACE: MEDIA FILTER; UV LAMP; HUM PAD; METAL INSERT
REMIND RESET
Top line: serv. req’d
Bot. line: action
SCHEDULE ON, SCHEDULE OFF, WAIT, FAN ON, FAN CIRC
MON SEP 24 3:OO PM
Top line: operation msgs
Bottom line: date & time
ROUTINE SYS CHECK−UP
REMIND RESET
Top line: serv. req’d
Bot. line: action
HOLD SETTING UNTIL PRESS SCHED TO
MON SEP 24 3:OO PM RESUME PROGRAM
[Alternating msgs during
a held schedule]
NO OUTDOOR SENSOR, HUM SENSOR ERROR, HVAC ERROR DETECTED
REMIND SERVICE
Top line: fault/error
Bot. line: action
DEALER INFORMATION (Edited to show dealer contact informa-
tion [2 lines])
Contact
Installing Dealer